The present invention relates to artificial feeding nipples, more specifically to one including incrementally adjustable flow rate.
Natural breastfeeding is unquestionably the best way to nurture an infant. Among the many benefits of breastfeeding, the way an infant suckles on the breast is important to proper muscle, speech and dental development. However, artificial feeding systems are appropriately used in many circumstances and should be designed to embrace the advantages of natural breastfeeding to the greatest extent possible.
For most of the past century, the majority of artificial feeding nipples have been made of latex and have been sold with a single aperture. The factory installed aperture in latex nipples could be enlarged by a care giver using a hot needle, and new apertures could likewise be added. Due in part to infants"" allergenic reactions to latex, silicone nipples have become increasingly popular in recent years. However, it is not safe for care givers to open additional apertures in silicone nipples as was formerly done with latex because of the tendency of silicone to tear. Consequently many manufacturers offer silicone nipples in a variety of flow specific rates. When an increase in flow rate is necessary or desirable, nipples with additional or larger apertures are purchased and the former nipples discarded. One such system is Dunn and Suarez, U.S. Pat. No. 5,544,766. Other novel approaches to flow control are cited by Duggal U.S. Pat. No. 5,667,084 and by Raymond, et al, U.S. Pat. No. 5,747,083. Hsu, U.S. Pat. No. 4,765,497 claims a nipple with tapered nubs appended to the outer surface which may be clipped back to incrementally increase flow. Appendage of the nubs to the exterior surface of the nipple necessitates unpleasant contact on the infant users"" sensitive palate, particularly once the protruding nubs have been partially clipped leaving distinct edges. A further drawback of this design is that as tapered apertures are opened at wider diameters, the nipple leaks far more readily. Three open apertures of say 0.010xe2x80x3 diameter each are much less likely to leak than one aperture providing an equal rate of flow.
Another important aspect of artificial nipple design is the way in which the baby latches on to the nipple and the suckling action required to draw fluid. White, U.S. Pat. No. 4,623,069 and Busnel, U.S. Pat. No. 5,673,806, both attempt to more closely simulate the muscle development and fluid flow common to natural breastfeeding. Artificial feeding nipples tend to collapse, sometimes to the point of completely closing the flow of fluid through them. As a result, manufacturers have installed ribs inside nipples to help prevent opposite sides of the tubular walls from fully contacting. Heller, U.S. Pat. No. 582,159 and McGeary, U.S. Pat. No. 1,588,846 are some early designs which may have prevented nipple collapse, but created unacceptable sanitation problems. The typical tubular nipple in use today can easily collapse, offering little resistance to an infant""s suckling action. This may result in impaired development of facial muscles, improper dental development and may even be the cause of later speech impediments.
Sanitation in infant feeding nipples is extremely important. The ideal nipple design would permit relatively easy access to all inner surfaces of the nipple for thorough cleaning and would prevent or minimize potential contamination of the outside surface while being stored. Nipple dust caps now frequently in use include a small cup on the inside surface to close the nipple when the dust cap is installed on the bottle, intending to prevent leakage while in transit. Some fluid inevitably leaks into the innermost surfaces of this cup, and being out of sight, the cavity is often left improperly cleaned. When the cap is re-installed, the clean nipple thus may be contaminated with bacteria growing in the recesses of the cap.
The preferred embodiment includes a nipple tube having an internal membrane which closes the tube while providing internal support against collapse. The membrane carries a plurality of small diameter apertures, only one of which is opened upon purchase. The closure nubs are turned inward to avoid contact with the infant""s palate or tongue, enabling incremental flow adjustment without exposed closure nubs. Using a single aperture requires a strong suck, and discourages babies who are breastfeeding from giving up the breast in favor of the bottle. As the infant matures, additional apertures are opened to increase flow without requiring purchase of new nipples.
The recessed tip encourages muscle development and provides a more pleasant, natural sensation in the mouth and on the palate of the infant user. It is easy to clean due to the shortened inner cavity and related ease of inverting the nipple tube. Also, there are no complex or inaccessible interior elements to pose cleaning problems. The recessed tip further includes a female annular sealing surface which allows the use of a small protrusion on the inside of the dust cap to sealingly plug the corresponding recess in the tip of the nipple. The improved seal is secure for travelling, while the plug is easy to clean, and is more likely to be noticed if contaminated.
A first object of the present invention is to provide incremental multiple flow options in a single nipple without external protrusions which might cause discomfort to the infant user. A second object is to provide a nipple that resists collapse and improves infant latch-on. A third object is to provide a nipple with a recessed tip which may be sealingly engaged by a corresponding nub in the dust cap to prevent leakage in transit. A fourth object is to provide a more sanitary nipple design that is easily cleaned. A fifth object is to provide a more sanitary nipple engagement member in the dust cap whereby there is no relatively inaccessible cavity to harbor bacteria. A sixth object is to provide a nipple that improves sensation on the infant user""s palate. A seventh object is to provide a platform for aperture closure nubs that can be accessed readily from the inside of the nipple. Further objects and advantages will become apparent upon review of the appended specification and drawing figures.